The immune system is the body’s biological defence to keep us healthy.1 It detects and destroys pathogens such as viruses or bacteria1 and is very good at identifying and destroying infected or unhealthy cells. However, sometimes the body needs extra assistance to recognise or fight intruders such as viruses or bacteria.1
Scientific advances have made it possible to enhance the body’s ability to produce pathogen-fighting cells or provide them directly to an individual.2,3
What are monoclonal antibodies and how are they used?
Antibodies are Y-shaped molecules produced naturally by the body’s immune system.4 They recognise, bind to and neutralise specific viruses and other pathogens.4,5
Monoclonal antibodies are produced in a laboratory to mimic or enhance the immune system's response.4 For more than 30 years, monoclonal antibodies have been approved and used to treat numerous diseases such as severe asthma, rheumatoid arthritis, Crohn’s disease, multiple sclerosis, infectious diseases and some types of cancer.7 In the setting of infectious diseases, monoclonal antibodies have the potential to provide almost immediate effect, making them potentially suitable for use in disease prevention as well as treatment.3,8,9
How are vaccines different from monoclonal antibodies for infectious diseases?
Monoclonal antibodies are often made from pathogen-specific immune cells of people who have recovered from an infection.10 They are highly specific and can be designed to identify and attack a particular disease-causing organism.11 Many copies of the antibody can be made and are usually given as an intravenous (IV) infusion or in some cases an injection.4
Vaccines use inactivated virus or bacteria or part of them to stimulate the body’s own immune response, including antibodies that help to recognise and destroy infected cells.12 As the immune system forms its own memory, vaccines essentially prime the body to fight a future infection if the person is later exposed to that particular pathogen.2 Vaccines are used to prevent a person from getting very sick from a particular illness in the future; they do not treat the illness.2
What is the difference between active versus passive immunity?
Vaccines are a type of active immunity.3 They require a healthy immune system and help jumpstart the body’s natural ability to produce infection-fighting cells.2
Monoclonal antibodies are a type of passive immunity.3 This means they are given directly to an individual to rapidly protect against or fight an illness rather than being produced by the body.3
How long does it take vaccines and monoclonal antibodies to work?
The immune response to a vaccine starts within days and develops over a few weeks.2 While a vaccine will train the immune system to battle future infections, monoclonal antibodies have the potential to provide almost immediate effect, neutralising intruders.2,6
How long do the effects of vaccines and monoclonal antibodies last?
Immunity from vaccines is typically long-lasting.3 Some vaccines may require multiple doses for continued protection.2
The duration of effect of a monoclonal antibody can vary and often needs to be administered numerous times throughout therapy.13 Scientists continue to develop new technologies to modify and enhance the duration of action of monoclonal antibodies. Antibodies can now be engineered to resist breakdown in cells.14 This can prolong the time they last in the circulation, increasing the amount of time the antibodies could protect against viruses and other pathogens.14-17 This may also lead to less frequent administration compared to traditional methods of engineering.14-17